MediaWiki REL1_28
MySQLMasterPos.php
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1<?php
10class MySQLMasterPos implements DBMasterPos {
12 public $file;
14 public $pos;
16 public $gtids = [];
18 public $asOfTime = 0.0;
19
25 function __construct( $file, $pos, $gtid = '' ) {
26 $this->file = $file;
27 $this->pos = $pos;
28 $this->gtids = array_map( 'trim', explode( ',', $gtid ) );
29 $this->asOfTime = microtime( true );
30 }
31
35 function __toString() {
36 return "{$this->file}/{$this->pos}";
37 }
38
39 function asOfTime() {
40 return $this->asOfTime;
41 }
42
44 if ( !( $pos instanceof self ) ) {
45 throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
46 }
47
48 // Prefer GTID comparisons, which work with multi-tier replication
49 $thisPosByDomain = $this->getGtidCoordinates();
50 $thatPosByDomain = $pos->getGtidCoordinates();
51 if ( $thisPosByDomain && $thatPosByDomain ) {
52 $reached = true;
53 // Check that this has positions GTE all of those in $pos for all domains in $pos
54 foreach ( $thatPosByDomain as $domain => $thatPos ) {
55 $thisPos = isset( $thisPosByDomain[$domain] ) ? $thisPosByDomain[$domain] : -1;
56 $reached = $reached && ( $thatPos <= $thisPos );
57 }
58
59 return $reached;
60 }
61
62 // Fallback to the binlog file comparisons
63 $thisBinPos = $this->getBinlogCoordinates();
64 $thatBinPos = $pos->getBinlogCoordinates();
65 if ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] ) {
66 return ( $thisBinPos['pos'] >= $thatBinPos['pos'] );
67 }
68
69 // Comparing totally different binlogs does not make sense
70 return false;
71 }
72
74 if ( !( $pos instanceof self ) ) {
75 throw new InvalidArgumentException( "Position not an instance of " . __CLASS__ );
76 }
77
78 // Prefer GTID comparisons, which work with multi-tier replication
79 $thisPosDomains = array_keys( $this->getGtidCoordinates() );
80 $thatPosDomains = array_keys( $pos->getGtidCoordinates() );
81 if ( $thisPosDomains && $thatPosDomains ) {
82 // Check that this has GTIDs for all domains in $pos
83 return !array_diff( $thatPosDomains, $thisPosDomains );
84 }
85
86 // Fallback to the binlog file comparisons
87 $thisBinPos = $this->getBinlogCoordinates();
88 $thatBinPos = $pos->getBinlogCoordinates();
89
90 return ( $thisBinPos && $thatBinPos && $thisBinPos['binlog'] === $thatBinPos['binlog'] );
91 }
92
99 protected function getGtidCoordinates() {
100 $gtidInfos = [];
101 foreach ( $this->gtids as $gtid ) {
102 $m = [];
103 // MariaDB style: <domain>-<server id>-<sequence number>
104 if ( preg_match( '!^(\d+)-\d+-(\d+)$!', $gtid, $m ) ) {
105 $gtidInfos[(int)$m[1]] = (int)$m[2];
106 // MySQL style: <UUID domain>:<sequence number>
107 } elseif ( preg_match( '!^(\w{8}-\w{4}-\w{4}-\w{4}-\w{12}):(\d+)$!', $gtid, $m ) ) {
108 $gtidInfos[$m[1]] = (int)$m[2];
109 } else {
110 $gtidInfos = [];
111 break; // unrecognized GTID
112 }
113
114 }
115
116 return $gtidInfos;
117 }
118
124 protected function getBinlogCoordinates() {
125 $m = [];
126 if ( preg_match( '!^(.+)\.(\d+)/(\d+)$!', (string)$this, $m ) ) {
127 return [ 'binlog' => $m[1], 'pos' => [ (int)$m[2], (int)$m[3] ] ];
128 }
129
130 return false;
131 }
132}
DBMasterPos class for MySQL/MariaDB.
int $pos
Binglog file position.
string[] $gtids
GTID list.
__construct( $file, $pos, $gtid='')
float $asOfTime
UNIX timestamp.
channelsMatch(DBMasterPos $pos)
string $file
Binlog file.
hasReached(DBMasterPos $pos)
This document is intended to provide useful advice for parties seeking to redistribute MediaWiki to end users It s targeted particularly at maintainers for Linux since it s been observed that distribution packages of MediaWiki often break We ve consistently had to recommend that users seeking support use official tarballs instead of their distribution s and this often solves whatever problem the user is having It would be nice if this could such as
We ve cleaned up the code here by removing clumps of infrequently used code and moving them off somewhere else It s much easier for someone working with this code to see what s _really_ going and make changes or fix bugs In we can take all the code that deals with the little used title reversing we can concentrate it all in an extension file
Definition hooks.txt:108
injection txt This is an overview of how MediaWiki makes use of dependency injection The design described here grew from the discussion of RFC T384 The term dependency this means that anything an object needs to operate should be injected from the the object itself should only know narrow no concrete implementation of the logic it relies on The requirement to inject everything typically results in an architecture that based on two main types of and essentially stateless service objects that use other service objects to operate on the value objects As of the beginning MediaWiki is only starting to use the DI approach Much of the code still relies on global state or direct resulting in a highly cyclical dependency which acts as the top level factory for services in MediaWiki which can be used to gain access to default instances of various services MediaWikiServices however also allows new services to be defined and default services to be redefined Services are defined or redefined by providing a callback the instantiator that will return a new instance of the service When it will create an instance of MediaWikiServices and populate it with the services defined in the files listed by thereby bootstrapping the DI framework Per $wgServiceWiringFiles lists includes ServiceWiring php
Definition injection.txt:37
An object representing a master or replica DB position in a replicated setup.